What did I want to do?
My objectives were simple; I wanted to make a comparison between two turf fertilizers.  One was a long-lasting product (Landscaper Pro ‘Full Season’ 22-5-5) labelled as having an 8-9 month longevity.  The second was an Organic Fertilizer product (12-5-11) labelled as having 5-8 week longevity.   Which would be better?  

How did I do this?
I set up a simple trial.  The trial would consist of putting down these fertilizers on 3m x 2m plots of a lawn and recording the results every week for 16 weeks.  
The chosen site was an award-winning garden in Lancashire, England.  The site had a large lawn with a mixture of grasses present surrounded by mixed borders with flowers and shrubs – this would be ideal.   The trial would run for 4 months from early May through to September.  A section of the lawn was marked out and the fertilizers were applied carefully by hand.  A very even application was achieved.   During the four months the plots would receive just a single application of Landscaper Pro ‘Full Season’, different plots would receive three applications of the organic fertilizer.   A calculation was made to ensure that the same amount of Nitrogen was applied to each plot over the duration of the trial. 

What did I learn?
The results were very clear.  Following application of the Landscaper Pro ‘Full Season’ the turf colour improved to a 'good' level, scored as above 6.0 out of 10.   The colour stayed at this ‘good’ level for the next 14 weeks.  The plots with the organic fertilizer improved in colour also following application to a ‘good’ level.  But the colour then dropped to below 5.0 out of 10 (rated as unsatisfactory) until the second application was made six weeks later.  The colour improved again after application and then dropped until the third application at the twelve week time.    Not only was the turf colour improved but the ‘Full Season’ plots stayed healthier, with less 'red-thread' disease developing.  This meant the plots looked much better too.

Why did I get these results?
The Landscaper Pro ‘Full Season’ is a fertilizer designed to release its nutrients to the turf slowly.  It is based on a 'coated' nutrient granule.  This sits in the turf and slowly and constantly releases a useful amount of Nitrogen, so the turf is constantly fed, and no nitrogen is washed away.  It is efficient and effective.  The organic fertilizer contains Nitrogen in a form which needs to be broken down by the soil microbes before it is available to the plant.  However, at the right soil temperature, and with reasonable soil moisture this can happen quickly. The nitrogen is released.  Some is used by the turf and some is lost from the soil.  It is less efficient and less effective.

So what is the conclusion? 
By making a single application of Landscaper Pro ‘Full Season’, I kept the turf at a better colour with less disease, for the whole summer.  It was rated as ‘good’ for 12 weeks.   It performed better than turf where three applications of an alternative organic fertilizer were made,  This was rated as ‘good’ for only 6 weeks yet had the same amount of Nitrogen.  There was a variable colour, and the turf developed more disease.   The Landscaper Pro Full Season is a more expensive fertilizer than the organic product (it is double the cost per kg), but the results from the whole summer made it more cost effective, giving a better lawn.